NTP via tcp?

SUSE Linux Enterprise Server SLES Networking
1

Hi,

is there a way to use the TCP-Protocol insteed of the UDP-Protocol for NTP
in SLES10/SLES11? (I know that TCP is not smart for NTP but the enviroment
use TCP for NTP :-\)

Bye

Bernd

2

Hi
You mean the time service on tcp port 37? You would need to enable time
and the xinetd service.

–
Cheers Malcolm °¿° (Linux Counter #276890)
openSUSE 12.2 (x86_64) Kernel 3.4.11-2.16-desktop
up 22:41, 3 users, load average: 0.00, 0.03, 0.05
CPU Intel® i5 CPU M520@2.40GHz | GPU Intel® Ironlake Mobile

3

malcolmlewis wrote:
[color=blue]

Hi
You mean the time service on tcp port 37? You would need to enable time
and the xinetd service.
[/color]

No,
I mean the Network Time Protocol on Port 123.

I assume that timeservice is outdated, isn’t it?

Bye

Bernd

4

Hi
The ntp protocol doesn’t/can’t use tcp only udp. So the server
you trying to sync to must be either time or daytime?

Maybe your time reference system is just using port tcp/123 maybe a
packet capture from tcpdump or wireshark might identify.

–
Cheers Malcolm °¿° (Linux Counter #276890)
openSUSE 12.2 (x86_64) Kernel 3.4.11-2.16-desktop
up 1 day 0:18, 3 users, load average: 0.10, 0.10, 0.06
CPU Intel® i5 CPU M520@2.40GHz | GPU Intel® Ironlake Mobile

5

[QUOTE=Bernd Nachtigall;11090]Hi,

is there a way to use the TCP-Protocol insteed of the UDP-Protocol for NTP
in SLES10/SLES11? (I know that TCP is not smart for NTP but the enviroment
use TCP for NTP :-\)

Bye

Bernd[/QUOTE]

Hi Bernd,

It’d be really interesting to know which “environment” makes use of TCP for NTP, as this violates the RFCs. The latest protocol definition for NTPv4 (RFC 5905) explicitly states in 7.3 that “the NTP packet is a UDP datagram”.

Regards,
Jens

6

jmozdzen wrote:

(…)[color=blue]

It’d be really interesting to know which “environment” makes use of TCP
for NTP, as this violates the RFCs. The latest protocol definition for
NTPv4 (RFC 5905) explicitly states in 7.3 that “the NTP packet is a UDP
datagram”.[/color]
(…)

There was a firewall which has blocked UDP. But now the service partner who
manage this part has corrected the settings. NTP runs fine now :slight_smile:

Thx for the RFC number!

Bye

Bernd